A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5965-01-628-4346
NSN 5998-01-210-6037
NSN 6145-01-279-9678
NSN 6145-00-505-7555
NSN 5905-01-040-4636
NSN 5998-00-462-2380
NSN 6645-01-521-3180
NSN 5960-01-169-1372
NSN 6105-00-205-0655
NSN 6130-01-484-3260
NSN 6105-01-145-5046
NSN 6105-01-629-4302